In a conventional electric vehicle, a prime mover such as a diesel engine, is used to drive an electric generator or alternator which supplies electric current to a plurality of electric motors. The electric motors typically are coupled to wheel sets, in line, on the vehicle. The vehicles that utilize this type of hybrid electric motor are typically railroad locomotives.
The prime mover drives the generator/alternator that typically produces an AC current that is then fully rectified with resulting DC current and voltage being distributed to current converters coupled to the electric motors. Such systems are highly integrated with each of the components typically designed and manufactured to operate with the other components in the overall system. In other words, “off the shelf” components are not readily adaptable for use in the initial design or ongoing maintenance of such vehicles. Further, such vehicles have multiple components associated with the change of AC to DC to AC power. Maintenance of such systems is expensive since specific components must be used.
In the use of hybrid drives for such electric vehicles, it is often necessary to add support systems such as pressurized lubrication and supplemental cooling for the motors and other components. Typically, these systems are centrally mounted on the vehicle and require the routing of specialized, pressurized, conduits to move the oil and coolant medium to specific points around the vehicle. Such additional equipment in conduit routings typically take up space that could be utilized for other purposes, such as cargo space. Such arrangements also are not cost effective since additional materials, i.e., conduits, pumps, filters, are required.
Thus there is a need for a self contained axle module for an electric vehicle that includes lubrication pump, filter, heat exchanger integrated into a single module. There is a further need for a self-contained axle module for a hybrid electric vehicle that is easy to replace and repair, particularly in the field. There is also a need for an electric vehicle that includes a self-contained axle module.